Concrete column cap



S. H. IN GBERG.

CONCRETE column CAP. APPLICATION FlLED- MAY 21, 1920-" 1,407,271Paitented Feb. 21, 1,922.

2 SHEETS-SHEET 1- S. H. INGBERG.

CONCRETE COLUMN CAP.

APPLICATION FILED MAY 2! Patented Feb. 21, '1922.

2 SHEETS-SHEET 2.

A'INT orrics. I

SIMON H. INGBERG, OF ELMHUBIST, ILLINOIS..

CONCRETE COLUMN GAP.

1920. Serial No. 383,072.

(nnmcarnn TO THE PUBLIC.)

cated to the free use of the Government ofv the United States and thepublic.

My invention relates to the details used for connecting columns andfloor beams in timber building construction and has for its object toprovide adequate and fire-resistive supports, in the form of reinforcedconcrete post caps, for connecting the columns of one 7 building storywith those above or below, as well as to provide by the same meansadequate and fire-resistivesupports for the floor members framing intothe caps near the columns.

In the accompanying drawings, which form a part of this specification,Figure 1 is a longitudinal section through the center of the two-wayreinforced concrete post cap taken on the line 1--1 of Figure 2;

Figure 2 is a cross section taken on the line 22 of Figure 1;

Figure 3 is a section through a portion of a timber floor construction,taken at theface of the columns on the line 3-3, Fig. 2, showing thetwo-way reniforced concrete post cap in place with reference to theother building members;

Figure 4 is an isometric view of the fourway reinforced concrete postcap.

Similar letters refer to similar parts throughout the several views.

Referring to Figures 1, 2 and 3, the central slab,A, supports thecolumns B and B on its lower and upper surface, respectively, and on theouter portions of its upper surface, the floor beams, C. Portions of theload reactions from the beams, C, and the bending strains induced bythem are transferred by shear to the outer ribs, D. The slab, A, andribs, D, constituting the body of the post cap, are made of Portlandcement concrete or other suitable fire-resistive" material having therequired mechanical strength. The slab, A, is reinforced with welded orexpanded metal mesh. Thebars, G, are added to give the required rigidityto the reinforcing frame, prior to embedment in the body material ofthecap. The reinforcing frame is supported in a mold of the requiredshape, which is filled with the body material, preferably in onecontinuous operation. On hardening of the filling, the reinforcingelements are firmly gripped and the two materials act ineffectivecombination to resist the stresses and strains imposed on the cap by thebeam and column loads.

Suitable recesses, H, are formed in the ribs, D, through which lagscrews, I, (Fig. 3) are threaded into the column and beam "ends to giveadded regidity to the construction.

The four-way cap shown in Figure 4 is made to receive floor beams onfour sides, the ends of the beams being sup-ported'on the upper surfaceof the outer ends of the slabs, A The columns bear against the lower andupper surfaces of the common central portion of the slabs, A their endsbeing contained within pockets formed inside of the ribs, D. The latterserve the same purpose as the ribs, D, of the two-way cap and thereinforcing details of the slabs and ribs are in effect the same in thefourway cap as described for the two-way cap.

By making the post caps of Portland cement concrete or othersimilarfire-resistive material, very little heat from a surrounding firewill be transmitted by the cap into the beam and column bearings,and thelatter will remain intact until the fire is exings soft and yielding,which results in failure at the bearing, due to cracking or slipping atthe cap, before the fire-resistance of the columnoutside of the cap hasbeen fully developed. The combination of design and material thatobviates failure at the bearings in case of exposure of the cap to fire,is an important part of my invention.

Having thus described my invention what. I claimis:

1. In a cap for timber columns, the combination of intimately connectedmembers of Portland cement concrete or other similar fire-resistivematerial, consisting of a hori- Specification of Letters Patent.Patented F b, 21 .jggg

Application filed ma 21,

zontal slab for receiving the timber column 7 and beam ends, verticalside rios extending above and below sald slab, connecting mem bersextending below sald slab and between sald ribs; and systems ofreinforcing bars embedded in sald slab, ribs, and connectmg Vmembers.

2. In a cap for timber columns, the combination of intimately connectedmembers of Portland cement concrete or other similar fire-resistivematerial, consisting of a horizontal slab for receiving the timbercolumn and beam ends, vertical side ribs extending above and below saidslab, connecting mem- V bearing surfaces against undue heating from apossible surrounding fire.

3. In timber building construction, the combination of timber columnsand timber floor members; a reinforced concrete column cap into whichsaid columns and floor members are framed; said cap being formed ofintimately connected members composed of Portland cement concrete orother similar fire-resistive material and consisting of a horizontalslab, vertical ribs, intermediate connecting members, and systemsofreinforcing bars embedded in said slab, ribs, and connecting'members;said slab, ribs and connecting members being arranged above, below andat the sides of said timber column and beam ends, thereby being adaptedto c protect their timber bearing surfaces against undue heating from apossible surrounding fire.

SIMON INGBERG.

